Vibrator



Patented June 25,1946

UNITED STATES PATENT v oar-ice Application March 18, 1944, Serial N0. 527,061

interrupters adapted to be operated at relatively high frequencies.

As those skilled in the art know, electromagnetic-vibratory interrupters are used at present on a substantial scale for converting current drawn from a low-voltage source into alternating current or relatively high voltage which after rectification may supply the plate circuits of radio transmitting and receiving equipment. It has been found to be advantageous to employ vibrators capable of being operated at relatively high frequencies as this made it possible to use transformers and filters of small dimensions. Great practical difficulties have been encountered, however, in the design and production of such high-frequency vibrators and although the suggestions and proposals in this direction have been quite numerous, none of these various suggestions and proposals was completely satisiactory and successful when carried into practice on a commercial scale.

It is an object of the present invention to provide a novel vibrator which overcomes the foregoing difllculties and which may be operated at relatively high frequencies.

It is another object of the present invention to provide a vibratory interrupter of novel and improved character having such balanced electrical, magnetic and mechanical organization as mature plates constituted of compliant ferromagnetic material.-

It is also within contemplation of the invention to provide a novel vibratory interrupter organization in which an individually compliant ferromagnetic armature plate is coordinated to each of two driver coils, said armature plates bearing vibratory contacts adapted to cooperate with substantially non-compllantly supported fixed contacts.

The invention also contemplates a high-frequency vibrator which is very simple in structure, positive and foolproof in operation, and which may be readily manufactured and sold on a practical and commercial scale .at a low cost.

Other and further objects and advantages of z lowing description, taken in conjunction. with the accompanying drawing; in which Fig. 1 illustrates a side elevational view of a preferred embodiment of the invention;

Fig. 2 depicts a front elevational view of the vibrator shown in Fig. 1:

Fig. 3 shows an end view of the vibrator embodylng the invention;

Fi 4 is a front elevational view of the vibratory structure forming part of the vibrator of the invention; and

Fig. 5 illustrates a circuit diagram of a preferred electrical circuit organization employed in connection with the vibrator shown in Figs. 1

While a preferred embodiment of the invention is described herein, it i contemplated that considerable variation may be made in the method of procedure and the construction of parts without departing from the spirit of the invention. In the following description, and in the claims, parts will be identified by specific names, for convenience, but they" are intended to be as generic in their application to similar parts as the art will permit.

Referring now more particularly to Figs. 1 to 4 or the drawing, in the preferred form of the invention a dual an symmetrically arranged driver coil system is used comprislngtwo flat strips or cores l0 constituted of ferromagnetic material. The upper ends of said cores constitute pole pieces II, while their lower ends I! are formed with lateral extensions in which there are provided holes H for stack screws M. A driver I coil I5 is surrounding each of cores Ill.

Progressing from one end, the stack comprises one of the core plates 12, metal spacer are, an insulative spacer It, a pair of substantially noncompliant side arms I! and It, insulative spacer stack is held together by means of two stack I screws l4 and nuts 28. At the ends of side arms l1, I8, 23 and 24 there are mounted fixed contacts 21, 28,29 and 30, respectively. The side arm are also provided with integrally formed soldering lugs II. Metal spacers 20 and 204 are preferably integrally formed of ferromagnetic metal strips bent to a U-shaped configuration. The object of these strips is to provide electrical connection between core plates l2 and the reed the invention will become apparent from the 101- to assembly. At the same time they also complete the magnetic circuit from the reed assembly to the core plates of the coils.

'I'he vibratory system is constituted of a hinge plate 2| having its lower portion conforming in shape to the lower portion I2 of the core plates Ill and having two holes 32 therein for the stack screws. The intermediate portion of the hinge plate is cut out at 33 as indicated to obtain a weakened portion 34 whereby there is obtained a degree-of rotational compliance, as this is more fully explained in my copending application Ser. No. 521,319 filed February 7, 1944. To the upper portion of the hinge plate there are secured two armature plate 35 with two interposed spacer plates 35 by means of rivet 31. The armature plates are constituted of compliant ferromagnetic sheet material, their lower portions extend vertically, their intermediate portions extend substantially horizontally toward pole pieces ll, while their end portions 38 are bent into parallel-spaced cooperating position with respect to said pole pieces. The upwardly extending portions of the armature plate have vibratory contacts 39, 40, 4i and 42 brazed thereon adapted to cooperate with the corresponding stationary contacts 21, 28, 29, and 30, respectively.

The circuit organization of the vibrator will appear from Fig. 5. It will be noted that the sourceof low voltage 50 has one of its terminals connected to the vibratory system at hinge plate 2|, while it other terminal is connected to the center tap or the primary winding 5| a transformer 52. The ends of the primary winding of the transformer are respectively connected to stationary interrupter contacts 21, 29' and also to one end oicoils ii. The other end of coils l are connected tohinge plate 2|.

The ends of secondary winding 53 of the trans former are respectively connected to stationary rectifier contacts 28 and 30. A buiier condenser 54 is connected across the secondary winding. The rectified output is taken oiI between terminals 55, one of which is connected to hinge plate 2 I, while the other is connected to the center tap oi the secondary winding. A capacitor-56 may be connected acrossthe output terminals in the conventional manner.

From the foregoing description the operation of the vibrator embodying the invention will be readily understood by those skilled in the art. It will be observed at the outset that upon closing the battery circuit, current will flow from one terminal of the battery through both halves of the primary w nding and through both coils back to the other terminal of the battery so that both coils will be simultaneously energized. Each coil will exert an oppositely directed force on its corresponding armature, plate 35 so that it would be expected that no displacement of the system of armature plates about hinge plate 21 will result. Experience, however, has surprisingly shown that the most minute asymmetry due to orientation, or possibly unequal magnetic forces, causes the system of armature plates to be deflected in one direction and that with a sufilciently compliant hinge sectionthe force is cumulative. This may be explained by considering that as soon as the most minute displacement oi the system of armature plates has taken place, this will move it further away from one pole piece and closer to the other pole piece so that the force in the direction in which the original displacement has taken place is strengthened, while the force in the opposite direction is weakened. thus causing further displacement in the initial direction. As-

suming that the initial displacement is in the direction of the coil 0n the left-hand side, deflection of the system of armature plates will continue until primary contact 21 is closed and thereby the corresponding coil is short-clrcuited.' This will disable one of the coils so that the field of the other will be controlling and will deflect the system of armature plates until primary contact 29 is closed and the other coil is deenergized, and so forth, whereby the vibratory system will be maintained in sustained oscillatory motion. It may be broadly stated that the predominating coil pulls its armature plate till contact is made and its travel has been limited by the contact pressure. The other armature plate maintains this contact pressure by its momentum and through its independent compliance. As this other armature plate swings back toward its own coil, its speed is reduced by the energy absorbed in accelerating the first armature plate and contacts. This results in a slow contact make which is a highly desirable mode of operation, To assure this mode of operation, the side arms carrying the fixed contacts are of a relatively noncompliant but at the same time adjustable character.

In order to provide self-rectifying operation 01. the vibrator, it is necessary that the rectifier contacts 28 and 30, make after the corresponding interrupter contacts 21 and 29, respectively, In prior self-rectifying vibrators, this was accomplished by introducing a sufiicient amount 0! compliance in the side arms or by mounting the vibratory contacts on auxiliary arms of suiiicient compliance. However, the compliance introduced into the vibratory system in this manner reduced the operating frequency and required that the ensuing harmonic oscillations either be tuned or dissipated during the off-contact period. It was found to be practically impossible to produce the desired high-frequency operation 01 the vibrator by these conventional expedients.

In the instant case, the proper timing oi the interrupter and rectifier contacts is obtained by introducing a slight degree of rotational compliance into the hinge section, carrying the armature plates, about the longitudinal axis thereof. This rotational compliance is obtained by providing a substantially weakened portion 34 in hinge plate 2|, between the clamped end 01 armature plates 35 and the clamped end of the hinged plate. In addition, the side arms carrying the fixed contacts are made substantially rigid and non-compliant and are so adjusted as to have the fixed interrupter contacts a little closer to the corresponding vibratory contacts than the rectifying contacts. Thus. during vibration of the armture plate assembly, the force due to the moving armature plate together with the interrupter contact pressure will form a couple which will slightly rotate the armature system about its longitudinal axis and will cause subsequent closure of the corresponding rectifier contact in the proper sequence. This structure and this type 0! sequential operation is more fully disclosed in my aforesaid application Ser. No. 521,319, to which reference is hereby made,

It will be noted that the vibrator of the invention provides important advantages. Thus, first of all, it comprises a two-coil arrangement with the obvious advantages of mechanical, magnetic and electrical symmetry. Also, the armatures work at the coil ends, which is the most eflective position. More energy is obtained by the armstures because more armature travel is obtained asoaars by having separately sprung armatures. 'I'he ma netic force acts through a greater distance 6 endsspacedlymoimtedinsaidstackandupwardly extending therefrom in parallel-spaced position,adrivercoilaroundeachotsaidcores,a

hingeplafeclampedinsaidstacksubstantially equidistantly from said cores, a pair of compliant ferromagnetic armature plates having one of their ends connected to the free end ofjsaid hinge plate, the main portion of said armature plates to cover the invention broadly within the spirit and scope of the appended claims.

What is claimed is:

1. An electromagnetic vibratory interrupter comprising in combination a pair of driver coils, an individually compliant contact-bearing armature for each of said coils having one of its ends freely and independently extending into the magneticfield of the respective coil, a hinge section in common for said armatures connected to the other end thereof and supporting them for vibration, fixed contacts adapted to" cooperate with,

the contacts on said armatures, substantially rigid mounting means for said fixed contacts, and connections constituting a symmetrical electrical system with said coils and'contacts alternately to energize and to disable said coils thereby to maintain said armatures in vibration when energy is suppliedto the system 2. An electromagnetic vibratory interrupter comprising in combination a pair of driver coils mounted inparallel-spaced position, a pole piece for each of said coils, an armature constituted of compliant ferromagnetic material for each of said coils and having a portion freely and independently extending into the magnetic field of the respective pole piece in close proximity thereof, a a

hinge plate in common for said armatures connected at one end to the other end of said armatures and fixed at its other end to support said armatures for joint vibration, vibratory contacts on each of said armatures, fixed contacts adapted to cooperate with said vibratory contacts. and substantially non-compliant mounting means for said fixed contacts, said coils and said fixed and vibratory contacts being connected into an electrical circuit alternately to energize and deener- 'giae said coils andtomaintain said armaturesin vibration when electrical energy is supplied to said circuit.

3. An electromagnetic vibratory interrupter in combination a stack, a pair of fer- 'romagneticcoreshavingoneoftheirendsspacsaidfixedcontactasaidcoilsandsaidfixedand armaturecontactsbeingadaptedtobeconnectcd intoscircuit alternatelytoenergiaeanddeenushell-idcoilsandtherebytomaintainsaidarmaturesinvibrationwheneleetricalenergyismppllcdtosaidcircuit.

4. An electromagnetic vibratory interrupter comprisingincombinationastacnapairofflat TIM plates for electrically and freely and independently extending upwardly and the terminal portions thereof being bent into opposite directions to extend into cooperating position with the free ends of the respective cores, vibratory contacts on said armature plates, a fixed cooperating contact for each of said vibratory contacts, and stack-clamped substantially non-compliant mounting means for said fixed contacts, said contacts being adapted to control a plurality of circuits including that of said coils thereby to maintain said armature plates in vibration.

5. An electromagnetic vibratory interrupter comprising in combination a stack, a pair of strips of ferromagnetic materialhaving one of their ends spacedly mounted in said stack and constituting pole pieces at their other end, a driver coil around each of said ferromagnetic strips, a hinge plate clamped in said stack substantially equidistantly from said strips, a pair of compliant ferromagnetic armature plates having one of their ends secured to the free end of said hinge plate but being capable of individual relative displacement at their other end, the lower portion of said armature plates extending upwardly substantially parallel with said strips, the intermediate portion thereof extending transversely. toward said pole pieces and the ends thereof extending into parallel-spaced cooperating position with-respect to said pole pieces. vibratory con- I tacts on said armature plates, a fixed cooperating contact ior each of said vibratory contacts, and

stack-clamped substantially non-compliant side arms for supporting said fixed contacts, said contacts being adapted to. control a plurality of circults including that of said coils thereby to maintain said armature plates in vibration.

6. A composite vibratory structure for an electromagnetic vibratory interrupter adapted to cooperate with a pair of driver coils for controling aplurality of circuits including that of said driver coils which comprises a hinge plate clamped at oneend thereof, and a pair of contact-bearing armature plates constituted of compliant ferromagnetic material having one of their ends connected to the free end of said hinge plate and having their other endfreely extending into the field of said coils, said armature plates being capable of limited but independent relative disedly mounted in said stack and having their other,

endextendingtherefromandconstitutingapolepiece,adrivercoilaroundeachofsaidcores,a hinge plate clamped in said stack substantially equidistantlyfromsaideores,apairofcompliant contact-bearing armature plates having one of theirendsconnectedtothefreeendofsaidhingc plate and having their other end freely and independentlyextcndingintoproximityoftherespective pole pieces, a fixed cooperating contact for each of said armature contactastack-clamped mountingmeansforsaidiixedcontacmandu- 7 magnetically connecting the clamped ends of said cores with the clamped end of said hinge plate.

8. An electromagnetic vibratory interrupter comprising in combination a pair 01' driver coils, a contact-bearing armature constituted oi! compliant/ferromagnetic material for each of said coils having one of its ends freely and independently extending into operative position with the respective coil, a hinge section in common for said armatures connected to the other end thereof and supporting them for vibration, relatively fixed contacts adapted to cooperate with said armature contacts. and connections constituting a symmetrical electrical system with said coils and contacts alternately to energize and to disable said coils thereby to maintain said arx'natures in vibration when energy is supplied to the system, said armatures being capable of limited relative displacement with respect to each other and to individually store and to non-synchronously release kinetic energy for causing slow contact "make and strong contact pressure immediately after contact make."

CLARENCE HUE'I'IEN. 

